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Endolysins, peptidoglycan hydrolases derived from bacteriophages (phages), are being developed as a promising alternative to conventional antibiotics. To obtain highly active endolysins, a diverse library of these endolysins is vital. We propose here microbial single-cell genome sequencing as an efficient tool to discover dozens of previously unknown endolysins, owing to its culture-independent sequencing method. As a proof of concept, we analyzed and recovered endolysin genes within prophage regions of Staphylococcus single-amplified genomes in human skin microbiome samples. We constructed a library of chimeric endolysins by shuffling domains of the natural endolysins and performed high-throughput screening against Staphylococcus aureus . One of the lead endolysins, bbst1027, exhibited desirable antimicrobial properties, such as rapid bactericidal activity, no detectable resistance development, and in vivo efficacy. We foresee that this endolysin discovery pipeline is in principle applicable to any bacterial target and boost the development of novel antimicrobial agents.

The Coleoptera Cerambycidae (longicorn beetles) use wood under different states (living healthy, freshly snapped, completely rot, etc.) in a species-specific manner for their larval diet. Larvae of some Cerambycidae groups have mycetomes, accessory organs associated with the midgut that harbor fungal symbiont cells. The symbionts are thought to improve nutrient conditions; however, this has yet to be shown experimentally. To deduce the evolutionary history of this symbiosis, we investigated the characteristics of the mycetomes in the larvae of longicorn beetles collected in Japan. Lepturinae, Necydalinae, and Spondylidinae are the only groups that possess mycetomes, and these three groups' mycetomes and corresponding fungal cells exhibit different characteristics between the groups. However, the phylogenetic relationship of symbiont yeasts does not coincide with that of the corresponding longicorn beetle species, suggesting they have not co-speciated. The imperfect vertical transmission of symbiont yeasts from female to offspring is a mechanism that could accommodate the host-symbiont phylogenetic incongruence. Some Lepturinae species secondarily lost mycetomes. The loss is associated with their diet choice, suggesting that different conditions between feeding habits could have allowed species to discard this organ. We found that symbiont fungi encapsulated in the mycetomes are dispensable for larval growth if sufficient nutrients are given, suggesting that the role of symbiotic fungi could be compensated by the food larvae take. Aegosoma sinicum is a longicorn beetle classified to the subfamily Prioninae, which does not possess mycetomes. However, this species contains a restricted selection of yeast species in the larval gut, suggesting that the symbiosis between longicorn beetles and yeasts emerged before acquiring the mycetomes.

The CLIP1-LTK fusion was recently discovered as a novel oncogenic driver in non-small cell lung cancer (NSCLC). Lorlatinib, a third-generation ALK inhibitor, exhibited a dramatic clinical response in a NSCLC patient harboring CLIP1-LTK fusion. However, it is expected that acquired resistance will inevitably develop, particularly by LTK mutations, as observed in NSCLC induced by oncogenic tyrosine kinases treated with corresponding tyrosine kinase inhibitors (TKIs). In this study, we evaluate eight LTK mutations corresponding to ALK mutations that lead to on-target resistance to lorlatinib. All LTK mutations show resistance to lorlatinib with the L650F mutation being the highest. In vitro and in vivo analyses demonstrate that gilteritinib can overcome the L650F-mediated resistance to lorlatinib. In silico analysis suggests that introduction of the L650F mutation may attenuate lorlatinib-LTK binding. Our study provides preclinical evaluations of potential on-target resistance mutations to lorlatinib, and a novel strategy to overcome the resistance., (© 2024. The Author(s).)

The cholecystokinin (CCK)/gastrin family peptides are involved in regulation of feeding and digestion in vertebrates. In the ascidian Ciona intestinalis type A (Ciona robusta), cionin, a CCK/gastrin family peptide, has been identified. Cionin is expressed exclusively in the central nervous system (CNS). In contrast, cionin receptor expression has been detected in the CNS, digestive tract, and ovary. Although cionin has been reported to be involved in ovulation, its physiological function in the CNS remains to be investigated. To elucidate its neural function, in the present study, we analyzed the expression of cionin and cionin receptors in the CNS. Cionin was expressed mainly in neurons residing in the anterior region of the cerebral ganglion. In contrast, the gene expressin of the cionin receptor gene CioR1, was detected in the middle part of the cerebral ganglion and showed a similar expression pattern to that of VACHT, a cholinergic neuron marker gene. Moreover, CioR1 was found to be expressed in cholinergic neurons. Consequently, these results suggest that cionin interacts with cholinergic neurons as a neurotransmitter or neuromodulator via CioR1. This study provides insights into a biological role of a CCK/gastrin family peptide in the CNS of ascidians., (© 2024. The Author(s).)

Apoptosis is a regulated cell death ubiquitous in animals defined by morphological features depending on caspases. Two regulation pathways are described, currently named the intrinsic and the extrinsic apoptosis. While intrinsic apoptosis is well studied and considered ancestral among metazoans, extrinsic apoptosis is poorly studied outside mammals. Here, we address extrinsic apoptosis in the urochordates Ciona, belonging to the sister group of vertebrates. During metamorphosis, Ciona larvae undergo a tail regression depending on tissue contraction, migration and apoptosis. Apoptosis begin at the tail tip and propagates towards the trunk as a polarized wave. We identified Ci-caspase 8/10 by phylogenetic analysis as homolog to vertebrate caspases 8 and 10 that are the specific initiator of extrinsic apoptosis. We detected Ci-caspase 8/10 expression in Ciona larvae, especially at the tail tip. We showed that chemical inhibition of Ci-caspase 8/10 leads to a delay of tail regression, and Ci-caspase 8/10 loss of function induced an incomplete tail regression. The specificity between apoptotic pathways and initiator caspase suggests that extrinsic apoptosis regulates cell death during the tail regression. Our study presents rare in vivo work on extrinsic apoptosis outside mammals, and contribute to the discussion on its evolutionary history in animals., (© 2024. The Author(s).)

Deuterostome invertebrates, including echinoderms, hemichordates, cephalochordates, and urochordates, exhibit common and species-specific morphological, developmental, physiological, and behavioral characteristics that are regulated by neuroendocrine and nervous systems. Over the past 15 years, omics, genetic, and/or physiological studies on deuterostome invertebrates have identified low-molecular-weight transmitters, neuropeptides and their cognate receptors, and have clarified their various biological functions. In particular, there has been increasing interest on the neuroendocrine and nervous systems of Ciona intestinalis Type A, which belongs to the subphylum Urochordata and occupies the critical phylogenetic position as the closest relative of vertebrates. During the developmental stage, gamma-aminobutylic acid, D-serine, and gonadotropin-releasing hormones regulate metamorphosis of Ciona. In adults, the neuropeptidergic mechanisms underlying ovarian follicle growth, oocyte maturation, and ovulation have been elucidated. This review article provides the most recent and fundamental knowledge of the neuroendocrine and nervous systems of Ciona, and their evolutionary aspects., Competing Interests: Declaration of competing interest The authors have no conflicts of interest., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Bilateria share sequential steps in their digestive systems, and digestion occurs in a pre-absorption step within a chamber-like structure. Previous studies on the ascidian Ciona intestinalis type A, an evolutionary research model of vertebrate organs, revealed that Ciona homologs of pancreas-related exocrine digestive enzymes (XDEs) are exclusively expressed in the chamber-like bulging stomach. In the development of the gastrointestinal tract, genes for the pancreas-related transcription factors, namely Ptf1a, Nr5a2, and Pdx, are expressed near the stomach. Recent organ/tissue RNA-seq studies on two Ciona species reported that transcripts of the XDE homologs exist in the intestinal regions, as well as in the stomach. In the present study, we investigated the spatial gene expression of XDE homologs in the gastrointestinal region of the C. intestinalis type A. Whole-mount in situ hybridization using adult and juvenile specimens revealed apparent expression signals of XDE homologs in a small number of gastrointestinal epithelial cells. Furthermore, two pancreas-related transcription factor genes, Nr5a2 and Pdx, exhibited multi-regional expression along the Ciona juvenile intestines. These results imply that ascidians may form multiple digestive regions corresponding to the vertebrate pancreas., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Echinoderms have long been utilized as experimental materials to study the genetic control of developmental processes and their evolution. Among echinoderms, the molecular study of starfish embryos has received considerable attention across research topics such as gene regulatory network evolution and larval regeneration. Recently, experimental techniques to manipulate gene functions have been gradually established in starfish as the feasibility of genome editing methods was reported. However, it is still unclear when these techniques cause genome cleavage during the development of starfish, which is critical to understand the timeframe and applicability of the experiment during early development of starfish., Results: We herein reported that gene functions can be analyzed by the genome editing method TALEN in early embryos, such as the blastula of the starfish Patiria pectinifera. We injected the mRNA of TALEN targeting rar, which was previously constructed, into eggs of P. pectinifera and examined the efficiency of genome cleavage through developmental stages from 6 to 48 hours post fertilization., Conclusion: The results will be key knowledge not only when designing TALEN-based experiments but also when assessing the results., (© 2023 American Association for Anatomy.)

Introduction: Sperm motility, including chemotactic behavior, is regulated by changes in the intracellular Ca 2+ concentration, and the sperm-specific Ca 2+ channel CatSper has been shown to play an important role in the regulation of intracellular Ca 2+ . In particular, in mammals, CatSper is the only functional Ca 2+ channel in the sperm, and mice deficient in the genes comprising the pore region of the Ca 2+ channel are infertile due to the inhibition of sperm hyperactivation. CatSper is also thought to be involved in sea urchin chemotaxis. In contrast, in ascidian Ciona intestinalis , SAAF, a sperm attractant, interacts with Ca 2+ /ATPase, a Ca 2+ pump. Although the existence of CatSper genes has been reported, it is not clear whether CatSper is a functional Ca 2+ channel in sperm. Results: We showed that CatSper is present in the sperm flagella of C. intestinalis as in mammalian species, although a small level of gene expression was found in other tissues. The spermatozoa of CatSper3 KO animals were significantly less motile, and some motile sperms did not show any chemotactic behavior. These results suggest that CatSper plays an important role in ascidians and mammals, and is involved in spermatogenesis and basic motility mechanisms., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kijima, Kurokawa, Sasakura, Ogasawara, Aratake, Yoshida and Yoshida.)

Objectives: To investigate whether the number and size of endometrial-leiomyoma fistulas (ELFs) change following uterine artery embolization (UAE) for leiomyoma and the correlation between ELFs and vaginal discharge (VD)., Materials & Methods: This study was a retrospective analysis of 100 patients who underwent UAE at a single institution between May 2016 and March 2021. They all underwent MRI at baseline, 4 months, and 1 year after UAE. The number and size of the ELFs were compared with the MRI images each time. The ELF tumor characteristics and the correlation between the ELFs and VD were assessed. Additional gynecologic interventions due to VD associated with ELFs were evaluated., Results: No ELF was observed at baseline. Ten ELFs were noted in nine patients at 4 months, and 35 ELFs were noted in 32 patients 1 year after UAE. The ELFs significantly increased over time (p = 0.004, baseline vs. 4 months; p < 0.001, 4 months vs. 1 year). The ELF size did not significantly change over time (p = 0.941). The tumors developing ELFs after UAE were mainly located at the submucosal or intramural area contacting the endometrium at baseline, with a mean size of 7.1 (2.6) cm. Nineteen patients (19%) had VD 1 year after UAE. There was no significant correlation between VD and the number of ELFs (p = 0.80). No patients underwent additional gynecologic interventions due to VD associated with ELFs., Conclusion: ELFs increased in number and did not disappear over time after UAE in most tumors., Clinical Relevance Statement: Despite the MR imaging findings, within the limited data of this study, ELFs were not seemingly associated with clinical symptoms, including VD., Key Points: • Endometrial-leiomyoma fistula (ELF) is a complication of uterine artery embolization (UAE). • ELFs increased in number over time after UAE and did not disappear in most tumors. • Most tumors developing ELFs after UAE were located near/contacted the endometrium and were larger., (© 2023. The Author(s), under exclusive licence to European Society of Radiology.)

Background: Ascidians significantly change their body structure through metamorphosis, but the spatio-temporal cell dynamics in the early metamorphosis stage has not been clarified. A natural Ciona embryo is surrounded by maternally derived non-self-test cells before metamorphosis. However, after metamorphosis, the juvenile is surrounded by self-tunic cells derived from mesenchymal cell lineages. Both test cells and tunic cells are thought to be changed their distributions during metamorphosis, but the precise timing is unknown., Results: Using a metamorphosis induction by mechanical stimulation, we investigated the dynamics of mesenchymal cells during metamorphosis in a precise time course. After the stimulation, two-round Ca 2+ transients were observed. Migrating mesenchymal cells came out through the epidermis within 10 min after the second phase. We named this event "cell extravasation." The cell extravasation occurred at the same time as the backward movement of posterior trunk epidermal cells. Timelapse imaging of transgenic-line larva revealed that non-self-test cells and self-tunic cells temporarily coexist outside the body until the test cells are eliminated. At the juvenile stage, only extravasated self-tunic cells remained outside the body., Conclusions: We found that mesenchymal cells extravasated following two-round Ca 2+ transients, and distributions of test cells and tunic cells changed in the outer body after tail regression., (© 2023 The Authors. Developmental Dynamics published by Wiley Periodicals LLC on behalf of American Association for Anatomy.)

Intestinal absorption is essential for heterotrophic bilaterians with a tubular gut. Although the fundamental features of the digestive system were shared among chordates with evolution, the gut morphologies of vertebrates diverged and adapted to different food habitats. The ascidian Ciona intestinalis type A, a genome-wide research model of basal chordates, is used to examine the functional morphology of the intestines because of its transparent juvenile body. In the present study, the characteristic gene expression patterns (GEP) of Ciona absorptive proteins, e.g., brush border membrane enzymes for terminal digestion (lactase, maltase, APA, and APN) and transporters (SGLT1, GLUT5, PEPT1, and B 0 AT1), were investigated in juveniles and young adults, with a special reference to the absorption of other nutrients by pinocytosis- and phagocytosis-related proteins (megalin, cubilin, amnionless, Dab2, Rab7, LAMP, cathepsins, and MRC1). Whole-mount in situ hybridization revealed that these GEP showed multi-regional and repetitive features along the Ciona gastrointestinal tract, mainly in the stomach and several regions of the intestines. In young adults, many absorption-related genes, including pinocytosis-/phagocytosis-related genes, were also expressed between the stomach and mid-intestine. In the gastrointestinal epithelium, absorption-related genes showed zonal GEP along the epithelial structure. Comparisons of GEP, including other intestinal functions, such as nutrient digestion and intestinal protection, indicated the repetitive assignment of a well-coordinated set of intestinal GEP in the Ciona gastrointestinal tract., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Invertebrates lack hypothalamic-pituitary-gonadal axis, and have acquired species-specific regulatory systems for ovarian follicle development. Ascidians are marine invertebrates that are the phylogenetically closest living relatives to vertebrates, and we have thus far substantiated the molecular mechanisms underlying neuropeptidergic follicle development of the cosmopolitan species, Ciona intestinalis Type A. However, no ovarian factor has so far been identified in Ciona . In the present study, we identified a novel Ciona -specific peptide, termed PEP51, in the ovary. Immunohistochemical analysis demonstrated the specific expression of PEP51 in oocyte-associated accessory cells, test cells, of post-vitellogenic (stage III) follicles. Immunoelectron microscopy revealed that PEP51 was localized in the cytosol of test cells in early stage III follicles, which lack secretory granules. These results indicate that PEP51 acts as an intracellular factor within test cells rather than as a secretory peptide. Confocal laser microscopy verified that activation of caspase-3/7, the canonical apoptosis marker, was detected in most PEP51-positive test cells of early stage III. This colocalization of PEP51 and the apoptosis marker was consistent with immunoelectron microscopy observations demonstrating that a few normal (PEP51-negative) test cells reside in the aggregates of PEP51-positive apoptotic test cells of early stage III follicles. Furthermore, transfection of the PEP51 gene into COS-7 cells and HEK293MSR cells resulted in activation of caspase-3/7, providing evidence that PEP51 induces apoptotic signaling. Collectively, these results showed the existence of species-specific ovarian peptide-driven cell metabolism in Ciona follicle development. Consistent with the phylogenetic position of Ciona as the closest sister group of vertebrates, the present study sheds new light on the molecular and functional diversity of the regulatory systems of follicle development in the Chordata., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The authors declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2023 Sakai, Yamamoto, Watanabe, Hozumi, Shiraishi, Osugi, Matsubara, Kawada, Sasakura, Takahashi and Satake.)

The control of cell numbers and the establishment of cell types are two processes that are essential in early embryonic development. We have a reasonable understanding of how these processes occur individually, but we have considerably less sophisticated understanding of how these processes are linked. Tunicates have fixed cell lineages with predictable cell cycles, making them well suited to investigate these processes. In the ascidian Ciona, we show that the transcription factor Zic-r.b, known to be involved in establishing several cell types in early development also activates the expression of the cell cycle inhibitor CDKN1B. Zic-r.b is a major missing component of the cell division clock establishing specific cell numbers. We also show that a larvacean homolog of Zic-r.b is expressed one cell cycle earlier than its Ciona counterpart. The early expression in larvaceans may explain why they have half as many notochord cells as ascidians and may illustrate a general mechanism to evolve changes in morphology., (Copyright © 2023. Published by Elsevier Inc.)

The ascidian Ciona intestinalis type A (or Ciona robusta) is an important organism for elucidating the mechanisms that make the chordate body plan. CRISPR/Cas9 and TAL effector nuclease (TALEN) are widely used to quickly address genetic functions in Ciona. Our previously reported method of CRISPR/Cas9-mediated mutagenesis in this animal has inferior mutation rates compared to those of TALENs. We here describe an updated way to effectively mutate genes with CRISPR/Cas9 in Ciona. Although the construction of TALENs is much more laborious than that of CRISPR/Cas9, this technique is useful for tissue-specific knockouts that are not easy even by the optimized CRISPR/Cas9 method., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)

The evolution of the biphasic life cycle in marine invertebrates has attracted considerable interest in zoology. We recently provided evidence that retinoic acid (RA) is involved in the regulation of metamorphosis in starfish. It also functions in life cycle transitions of jellyfish (cnidaria). Thus, documenting the evolutionarily conserved role of RA in such transitions will help to trace the life cycle evolution of bilaterians and cnidarians. In this study, we examined the molecular mechanisms by which RA signaling is involved in the commencement of metamorphosis in starfish. First, we measured RA levels during the larval and metamorphosis stages by liquid chromatography-tandem mass spectrometry. We found that all-trans RA levels in the larval body are high before larvae acquire competence for metamorphosis, suggesting that the commencement of metamorphosis is not controlled by increased RA synthesis. Furthermore, the suppression of rar gene expression by TALEN-mediated gene knockout revealed that RA receptor (RAR) is essential for metamorphosis. These observations suggest that the initiation of metamorphosis is regulated at the level of synthesized RA to activate RAR. We discuss the divergence of ligand molecules and receptors during the evolution of life cycle regulation., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Due to similarities in iodine concentrations and peroxidase activities, the thyroid in vertebrates is considered to originate from the endostyle of invertebrate chordates even though it is a glandular (mucus-producing) organ for aquatic suspension feeding. Among chordates with an endostyle, urochordates are useful evolutionary research models for the study of vertebrate traits. The ascidian Ciona intestinalis forms an endostyle with specific components of glandular- and thyroid-related elements, and molecular markers have been identified for these components. Since we previously examined a simple endostyle in the larvacean Oikopleura dioica, the expression of the thyroid-related transcription factor genes, Ciona Nkx2-1 and FoxE, was perturbed by TALEN-mediated gene knockout in the present study to elucidate the shared and/or divergent features of a complex ascidian endostyle. The knockout of Ciona Nkx2-1 and FoxE exerted different effects on the morphology of the developing endostyle. The knockout of Nkx2-1 eliminated the expression of both glandular and thyroidal differentiation marker genes, e.g., vWFL1, vWFL2, CiEnds1, TPO, and Duox, while that of FoxE eliminated the expression of the differentiation marker genes, TPO and CiEnds1. The supporting element-related expression of Pax2/5/8a, Pax2/5/8b, FoxQ1, and β-tubulin persisted in the hypoplastic endostyles of Nkx2-1- and FoxE-knockout juveniles. Although the gene regulation of ascidian-specific CiEnds1 remains unclear, these results provide insights into the evolution of the vertebrate thyroid as well as the urochordate endostyle., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Metamorphosis is the dramatic and irreversible reconstruction of animal bodies transitioning from the larval stage. Because of the significant impact of metamorphosis on animal life, its timing is strictly regulated. Invertebrate chordate ascidians are the closest living relatives of vertebrates. Ascidians exhibit metamorphosis that converts their swimming larvae into sessile adults. Ascidian metamorphosis is triggered by a mechanical stimulus generated when adhesive papillae adhere to a substrate. However, it is not well understood how the mechanical stimulus is generated and how ascidian larvae sense the stimulus. In this study, we addressed these issues by a combination of embryological, molecular, and genetic experiments in the model ascidian Ciona intestinalis Type A, also called Ciona robusta. We here showed that the epidermal neuronal network starting from the sensory neurons at the adhesive papillae is responsible for the sensing of adhesion. We also found that the transient receptor potential (TRP) channel PKD2 is involved in sensing the stimulus of adhesion. Our results provide a better understanding of the mechanisms underlying the regulation of the timing of ascidian metamorphosis., (© 2022 Japanese Society of Developmental Biologists.)

The phylogenomic approach has largely resolved metazoan phylogeny and improved our knowledge of animal evolution based on morphology, paleontology, and embryology. Nevertheless, the placement of two major lophotrochozoan phyla, Entoprocta (Kamptozoa) and Ectoprocta (Bryozoa), remains highly controversial: Originally considered as a single group named Polyzoa (Bryozoa), they were separated on the basis of morphology. So far, each new study of lophotrochozoan evolution has still consistently proposed different phylogenetic positions for these groups. Here, we reinvestigated the placement of Entoprocta and Ectoprocta using highly complete datasets with rigorous contamination removal. Our results from maximum likelihood, Bayesian, and coalescent analyses strongly support the topology in which Entoprocta and Bryozoa form a distinct clade, placed as a sister group to all other lophotrochozoan clades: Annelida, Mollusca, Brachiopoda, Phoronida, and Nemertea. Our study favors the evolutionary scenario where Entoprocta, Cycliophora, and Bryozoa constitute one of the earliest branches among Lophotrochozoa and thus supports the Polyzoa hypothesis.

d-Serine, a free amino acid synthesized by serine racemase, is a coagonist of N -methyl-d-aspartate-type glutamate receptor (NMDAR). d-Serine in the mammalian central nervous system modulates glutamatergic transmission. Functions of d-serine in mammalian peripheral tissues such as skin have also been described. However, d-serine's functions in nonmammals are unclear. Here, we characterized d-serine-dependent vesicle release from the epidermis during metamorphosis of the tunicate Ciona . d-Serine leads to the formation of a pocket that facilitates the arrival of migrating tissue during tail regression. NMDAR is the receptor of d-serine in the formation of the epidermal pocket. The epidermal pocket is formed by the release of epidermal vesicles' content mediated by d-serine/NMDAR. This mechanism is similar to observations of keratinocyte vesicle exocytosis in mammalian skin. Our findings provide a better understanding of the maintenance of epidermal homeostasis in animals and contribute to further evolutionary perspectives of d-amino acid function among metazoans.

The demand for raspberry ketone (RK) as a plant-based natural flavoring agent is high, but natural RK is one of the most expensive flavor compounds due to its limited content in plants. Here, we produced RK de novo from simple carbon sources in Escherichia coli. We genetically engineered E. coli metabolism to overproduce the metabolic precursors tyrosine and p -coumaric acid and increase RK production. The engineered E. coli produced 19.3- and 1.9 g/L of tyrosine and p -coumaric acid from glucose, respectively. The p -coumaric acid CoA ligase from Agrobacterium tumefaciens and amino acid substituted benzalacetone synthase of Rhemu palmatum (Chinese rhubarb) were overexpressed in E. coli overproducing p -coumaric acid . The overexpression of fabF , encoding β-ketoacyl-acyl carrier protein synthetase II increased intracellular malonyl-CoA, the precursor of benzalacetone synthase for RK biosynthesis, and improved RK production. Fed-batch cultures given glucose as a carbon source produced 62 mg/L of RK under optimized conditions. Our production system is inexpensive and does not rely on plant extraction; thus, it should significantly contribute to the flavor and fragrance industries., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Masuo, Saga, Usui, Sasakura, Kawasaki and Takaya.)

The protovertebrate Ciona intestinalis type A (sometimes called Ciona robusta ) contains a series of sensory cell types distributed across the head-tail axis of swimming tadpoles. They arise from lateral regions of the neural plate that exhibit properties of vertebrate placodes and neural crest. The sensory determinant POU IV/Brn3 is known to work in concert with regional determinants, such as Foxg and Neurogenin , to produce palp sensory cells (PSCs) and bipolar tail neurons (BTNs), in head and tail regions, respectively. A combination of single-cell RNA-sequencing (scRNA-seq) assays, computational analysis, and experimental manipulations suggests that misexpression of POU IV results in variable transformations of epidermal cells into hybrid sensory cell types, including those exhibiting properties of both PSCs and BTNs. Hybrid properties are due to coexpression of Foxg and Neurogenin that is triggered by an unexpected POU IV feedback loop. Hybrid cells were also found to express a synthetic gene battery that is not coexpressed in any known cell type. We discuss these results with respect to the opportunities and challenges of reprogramming cell types through the targeted misexpression of cellular determinants., Competing Interests: The authors declare no competing interest., (Copyright © 2022 the Author(s). Published by PNAS.)